Vasectomy
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Background | |
B.C. type | Sterilization |
First use | 1897 (experiments from 1785)[1] |
Failure rates (first year) | |
Perfect use | <0.1% |
Typical use | 0.15% |
Usage | |
Duration effect | Permanent |
Reversibility | Often possible, but not always. |
User reminders | Additional methods required until 2 negative semen samples. Almost all failures are due to disregarding this instruction. |
Clinic review | None |
Advantages and Disadvantages | |
STD protection | No |
Benefits | Local anesthetic to the scrotum and vasa deferentia by needle or jet injection, as opposed to general anesthesia usually needed for female sterilization. |
Risks | Risk of chronic pain, incidence and severity is widely debated. |
Vasectomy is a surgical procedure in which the vasa deferentia of a man are cut for the purpose of sterilization.
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There are some variations on the procedure such as no-scalpel (keyhole) vasectomies,[2] in which a sharp hemostat, rather than a scalpel, is used to puncture the scrotum. Another type of vasectomy which may reduce the risk of chronic pain is called an "open ended" vasectomy. A "normal" vasectomy typically seals both ends of the vas deferens with stitches, heat, metal clamps or a combination, after cutting. The open-ended vasectomy obstructs only the top end of the vas deferens. With this method sperm leaks out from the lower severed end of the vas deferens and into the scrotum, thus hopefully avoiding a build-up of pressure in the epididymis. The likelihood of long-term testicular pain from "backup pressure" seems to be reduced using this method.[3]
After vasectomy, the testes remain in the scrotum where Leydig cells continue to produce testosterone and other male hormones that continue to be secreted into the blood stream. Some studies find that sexual desire is unaffected in over 90% of vasectomized men,[4] whereas other studies find higher rates of diminished sexual desire.[5] The sperm-filled fluid from the testes contributes about 10% to the volume of an ejaculation (in men who are not vasectomized) and does not significantly affect the appearance, texture, or smell of the ejaculate.[6]
When the vasectomy is complete, sperm can no longer exit the body through the penis. The testicles continue to produce sperm, but they are broken down and absorbed by the body. Much fluid content is absorbed by membranes in the epididymis, and much solid content is broken down by the responding macrophages and re-absorbed via the blood stream. Sperm is matured in the epididymis for about a month once it leaves the testicles. Approximately 50% of the sperm produced never make it to the orgasmic stage in a non-vasectomized man. After vasectomy, the membranes increase in size to absorb and store more fluid; this triggering of the immune system causes more macrophages to be recruited to break down and re-absorb more of the solid content. Within one year after a vasectomy, sixty to seventy percent of vasectomized men develop antisperm antibodies. In some cases, vasitis nodosa, a benign proliferation of the ductular epithelium, can also result.[7][8] The buildup of sperm increases pressure in the vas deferens and epididymis. To prevent damage to the testes, these structures eventually rupture in more than half the cases. The entry of the sperm into the scrotum causes sperm granulomas to be formed by the body to contain and absorb the sperm which the body treats as a foreign substance.[9]
Early failure rates, i.e. pregnancy within a few months after vasectomy, are below 1%, but the effectiveness of the operation and rates of complications vary with the level of experience of the surgeon performing the operation and the surgical technique used.
Although late failure, i.e. pregnancy after recanalization of the vasa deferentia, is very rare, it has been documented.[10]
Worldwide, approximately 6% of married women using contraception rely on vasectomy.[11]
The rate of vasectomies compared to tubal ligations worldwide is extremely variable among countries, and the statistics are mostly based on questionnaire studies rather than actual counts of procedures performed. Worldwide, approximately five times as many married women rely on female sterilization as those relying on male sterilization.[11] In the U.S. about 3 times as many women at risk for unintended pregnancy rely on tubal ligation as on vasectomy.[12] In the U.S. tubal ligation is used more frequently than vasectomy, although the proportions vary from state to state.[13] In Britain, vasectomy is more popular than tubal ligation, though this statistic may be as a result of the data-gathering methodology.
Couples who opt for tubal ligation do so for a number of reasons, including:
Couples who choose vasectomy are motivated by, among other factors:[14]
Short-term complications include temporary bruising and bleeding, known as hematoma. The primary long-term complication is a permanent feeling of pain - Post-Vasectomy Pain Syndrome.
Animal and human data indicate that vasectomy does not increase atherosclerosis and that increases in circulating immune complexes after vasectomy are transient. Furthermore, the weight of the evidence regarding prostate and testicular cancer suggests that men with vasectomy are not at increased risk of these cancers.[17]
Post-Vasectomy Pain Syndrome (PVPS), genital pain of varying intensity that may last for a lifetime, is estimated to appear in between 5% and 35% of vasectomized men, depending on the severity of pain that qualifies for the particular study[18][19][20][21] The pain can be orchialgia, pain with intercourse, ejaculation, or physical exertion, or tender epididymides.[22] In one study, vasectomy reversal was found to be 69% effective for reducing the symptoms of chronic post-vasectomy pain. Treatment options for 31% of patients whose pain did not respond to vasectomy reversal were limited. The study was very small, only evaluating 13 patients, making it difficult to draw solid conclusions.[23] In severe cases castration has been resorted to.[24]
Researchers reported in February 2007 that a survey of a small number of men with primary progressive aphasia, a rare speech disorder, found that more than twice as many as would be expected had undergone vasectomies.Because primary progressive aphasia is so rare compared to the number of men undergoing vasectomy it is statistically very unlikely that any one individual would develop this problem. Twice as much of a very small number is still a very small number. The study has not yet been verified by other researchers, and the authors say larger studies are needed to better understand the issue.[25]
Some men experience depression or anger and go through a period of mourning over the loss of their reproductive ability. This emotion is similar to what some women experience after menopause. Approximately half of all vasectomized men prefer to keep their sterilization secret. [26] Depending upon the study, between five and eleven percent of men regret the decision to have a vasectomy.[27]
Although men considering vasectomies should not think of them as reversible, and most men and their spouses are satisfied with the operation, [28][29][30] there is a procedure to reverse vasectomies using vasovasostomy (a form of microsurgery first performed by Earl Owen in 1971[31][32]). Vasovasostomy is effective at achieving pregnancy in only 50%-70% of cases, and it is very costly, with total out-of-pocket costs in the United States of approximately $7,000 [33]. The rate of pregnancy depends on such factors as the method used for the vasectomy and the length of time that has passed since the vasectomy was performed. The reversal procedures are frequently impermanent, with occlusion of the vas recurring two or more years after the operation.
Since the body often produces antibodies against sperm, sperm counts are rarely at pre-vasectomy levels. There is evidence that men who have had a vasectomy may produce more abnormal sperm, which would explain why even a mechanically successful reversal does not always restore fertility.[34][35] The higher rates of aneuploidy and diploidy in the sperms of men who have undergone vasectomy reversal may lead to a higher rate of birth defects [36].
In order to allow a possibility of reproduction (via artificial insemination) after vasectomy, some men opt for cryostorage of sperm before sterilization.[37]
The vasectomy is also covered in Canada.
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